1. Field of the Invention
The present invention relates to an apparatus and process for heating and/or cooling of the intake air to a combustion gas turbine. More particularly the invention relates to a skid mounted modular unit that is manufactured off site and transported to the turbine location and connected with a minimum of on site construction. Most particularly the invention relates to a process and apparatus that utilize the exhaust heat from the turbine to indirectly heat the intake air to the turbine.
2. Related Information
In industry combustion gas turbines (C.G.T.""s) drive a variety of devices (i.e., generators, gas compressors, pumps, etc.) and are subject to continually changing ambient conditions, which can adversely affect their power output. The combustion gas turbine industry has always struggled with controlling the power of the turbine at varying intake ambient air temperatures. Some problems listed below (not all inclusive) are typical of users of combustion gas turbines have struggled with since the development of the combustion gas turbine:
1. Varying inlet temperatures resulting in varying combustion gas turbine power outputs and thus unpredictable work produced.
2. Varying temperatures related to increased maintenance and operating costs.
3. Conventional inlet chilling (using basic liquid chillers) and heating costs were high.
4. Conventional inlet chilling using basic liquid chillers of the reciprocating, screw or centrifugal type refrigeration compressors were not large enough regarding capacity to cool the combustion gas turbine large mass flow rates with redundant systems.
5. Basic liquid chillers with their ancillary components (pumps, cooling tower, electrical switchgear, piping, control systems, sound components, weatherproofing costs, buildings, civil work, and field assemble labor) required large physical areas to field assemble.
6. Field erected systems have been undependable with regard to guaranteed performance and parasitic electrical loads of the systems have been too high to justify installation.
7. Alternate methods of inlet cooling, such as evaporative cooling or water atomization into the combustion gas turbine inlet, while low in initial cost, do not maintain steady inlet temperatures with varying ambient conditions. Since these methods are completely dependent on evaporation of water, the higher the wet bulb temperature, the less effectively they cool. It is typically at high wet bulb temperature conditions that maximum combustion gas turbine output is needed.
The present invention comprises a modular unit in which all of the components necessary for conditioning the intake air for a combustion gas turbine are contained. The compressors, evaporators condensers and related pumps and control equipment are contained within a weather proof enclosure having sound insulation installed in the walls.
There are many aspects of the present invention that are unique and that have not been known in the prior art. These novel features include but are not limited to:
1. A single lift packaged modular combustion gas turbine chilling, control and monitoring system that can be installed without the use of (a) multiple disciplines, (b) engineering and construction site contractors, (c) untested products, (d) multi component vendors (i.e., chillers, pumps, controls, electrical components, etc.), (d) guesswork, (f) field welding, (g) insulation, (h) piping, (i) instrumentation, (j) structural systems, (k) weatherproofing and (I) provisions for extreme systems.
2. The present modular system is different from field erected systems in that it:
(a) can be operated in hazardous environments without costly xe2x80x9cexplosion proofingxe2x80x9d electrical modifications.
(b) responds directly to C.G.T. operator""s inlet air temperature sensing which is part of the operator""s digital control system (D.C.S.). Field erect systems typically respond to chilling fluid temperatures.
(c) provides electrical parasitic load (KW) data directly to operator""s D.C.S. console.
(d) provides auto-switchover of 100% stand-by pump on condender water or chilling liquid. Field erect systems require operator manual changeover with valves.
(e) provides the entire process in fully weatherproof, thermally insulated, and sound attenuated enclosures. Field erected systems offer none of these items and require a building to provide any protection. Field erect systems offer no integrated modular designs on cooling and no optional integrated C.G.T. inlet heating modules for direct integration into the chilling process by way of:
1. control system
2. piping and valves
3. heat exchanger
4. electrical system
5. commonality of components
(f) provides compact, single lift modules, factory assembled, tested, and transportable on major highways to any site.
(g) provides portable modules, easily moved to other sites and quickly connected for operation.
(h) provides large capacity (cooling tons) modules which use simple 2-flow pass heat exchangers on liquid chilling and condensers, eliminating extensive and complicated series and parallel flow arrangements common to some field erected systems.
(i) provides available multiple centrifugal compressors on single heat exchanger vessels for stand-by capability (50%/50%) and very efficient operation at partial loads. No other system offers this.
(j) provides fully independent microprocessor control and safety logic for each centrifugal compressor.
(k) uses R-134a xe2x80x9cchlorine freexe2x80x9d refrigerant in capacities over 1,500 tons, an exclusive.
(l) has the ability to control module temperature (ventilation, cooling, heating, and/or humidity control) surrounding all process system components so they are not affected by changing outdoor weather, and exclusive.
(m) is fully assembled, pre-piped, pre-wired, insulated, and tested prior to shipment, and exclusive.
(n) has the ability to reclaim C.G.T. exhaust heat through thermal oil/E.G. liquids and provide heating at C.G.T. inlet with the common components of the chilling system is unique to this process.
(o) provides centrifugal compressors on liquid chilling systems are aircraft derivative design for fast start and fast stop of compressors, saving energy and eliminating costly xe2x80x9ccoast downxe2x80x9d lubrication systems.
(p) provides single point power connections for entire system electrical distribution, safety, back up, and operation, a unique feature.
(q) provides reclaiming inlet chilling coil condensate to cooling tower make-up water stream for less make-up water usage and to improve tower efficiency.